Method of removing pipe



Nov. 16, 1965 BQYER METHOD OF REMOVING PIPE Original Filed Sept. 7, 1962.N-Q-t h- \Q g |u INVENTOR Louis B. Boyer BY W W Ma ATTORNEYS UnitedStates Patent Ufifrce 3,217,816 Patented Nov. 16, 1965 3,217,816 METHODOF REMOVING PIPE Louis B. Boyer, 9531 N. Green Court, Westrninister,Colo. Continuation of application Ser. No. 221,976, Sept. 7, 1962. Thisapplication Dec. 10, 1964, Ser. No. 419,274 3 Claims. (Cl. 175-57) Thisapplication is a continuation of my copending application, Serial No.221,976, filed September 7, 1962, now abandoned.

This invention relates to a masonry drill and more in particular to adrill for removing pipe from a wall.

Heretofore it has been necessary to remove a large section of the wallto remove therefrom a pipe which has broken close to or flush with thewall surface. Attempts to drill in masonry from around the exteriorsurface of the pipe have not been satisfactory, because of the excessivechattering, which usually leads to the rupture of the pipe wall.

The tool described herein is a rotary tool and does not operate on thepercussion principle employed in removing drill stems, as shown in theSitton et a1. Patent No. 2,827,264; neither does it operate on the sameprinciple as a core bit, such as used in drilling oil wells. Masonrydrills, as shown in the Chapin Patent No. 2,856,157 and Tilden PatentNo. 2,506,474 are not suitable for removing pipes from a masonry wall.

Very often in new construction, or in domestic installation a surfacepipe will become broken at the point of entry to the wall and there willbe no access to the waterproofing on the outside 'of the wall. It willtherefore become desirable to remove this pipe from the only point ofaccess.

It is an object of the present invention to provide a tool which willremove a pipe from a masonry wall.

It is a further object of this invention to provide a drilling bit whichwill not only remove a small section of the wall adjacent the pipe butremove a small amount of the surface of the pipe.

It is a still further object of this invention to provide a drilling bitthat may be operated by a standard electric drill.

The various features of novelty which characterize the present inventionare pointed out with particularity in the claims annexed to and forminga part of this specification. However, for a better understanding of theinvention, and its advantages and specific objects in the use thereof,reference is made to the accompanying drawings and descriptive matterwherein is illustrated and described a preferred embodiment of theinvention.

In the drawings:

FIGURE 1 is a schematic view of the invention, showing the drill bit andthe wall.

FIGURE 2 is a side view, partially in section, showing the bit.

FIGURE 3 is an end view of the bit shown in FIG URE 1.

FIGURE 4 is a view, partially in section, showing the bit and the wallwith the pipe in place.

A drill bit is composed of a barrel section 11 having teeth 12, 12,around the end circumference thereof and having a shank portion 13 onits opposite end.

The teeth may be made of hardened steel or of cemented carbide, and arefixed to the barrel section around the leading end thereof. These teethmay be set with a pitch or rake angle 9, shown in FIGURE 3 of 0 to 8degrees to aid in their cutting action. The slank or trailing endportion 13 may be threaded or may be welded to the barrel portion 11 andhas a stud 14 on the end thereof of such a diameter that it may bereceived by a standard electric drill. The inside diameter of the bit issmaller than the pipe by 10 to 20 mils, so that the interior cuttingsurface 15 of the teeth 12 remove the exterior surface of the pipe 16.This acts as a guide and prevents chattering of the tool when theexterior surface 17 and the end surface 18 of the teeth 12 come intocontact with the masonry wall 19. This permits a smooth even cut of thetool through the wall and the removal of the pipe 16 therefrom when thewall has been breached.

In operation, the tool 10 is fixed to the electric drill 20 by means ofthe stud 14 being received in and held by the chuck 21. The drill isthen brought into contact with the pipe 16, as shown in FIGURE 1. Theinterior surface of the drill teeth mill the pipe and the pipe acts as aguide for the drill bit, which when advanced along the pipe, as shown inFIG. 4 mills the wall 19 from around the pipe.

A drill bit for use on a three-fourth inch pipe is one andseven-sixteenth inches outside diameter and can vary from twelve toforty-eight inches in length. The inside diameter of the cutting teethas pointed out above is slightly less than the outside diameter of thepipe so as to remove therefrom 10 to 20 mils of the pipe wall.

While in accordance with provisions of the statutes, there has beenillustrated and described the best form of embodiment of this inventionnow known, it will be apparent to those skilled in the art that changesmay be made in the form or size "of the apparatus disclosed withoutdeparting from the spirit of this invention as set forth in the appendedclaims and that in some cases certain features of the invention may beused to advantage without a corresponding use of other features.

What is claimed is:

1. A method of removing a pipe embedded in a masonary wall whichcomprises the steps of:

(a) contacting said wall with said pipe embedded therein, at the pointat which said pipe is embedded in said wall, with a rotary drill bithaving an axial bore and a plurality of elongated cutting teeth whichextend substantially along the interior and exterior surfaces of saidbit at the leading end thereof and which are rigidly attached to saidleading end of said bit, said cutting teeth having an interior diameterof from 10 to 20 mils less than the outside diameter of said pipe, andan outside diameter greater than the outer diameter of said bit and aninner diameter less than the inner diameter of said bit, said cuttingteeth having a pitch of 0 to 8 degrees, said bit being attached at thetrailing end thereof to a rotary tool;

(b) moving said drill bit coaxially of said pipe so as the axial bore ofsaid drill bit from the breach in bit using said pipe as a guide meansfor guiding the movement of said drill bit into said wall and coaxiallyof said pipe in such a manner as to remove from 10 to 20 mils of theexterior surface from such pipe during the drilling operation; and

(c) removing said drill bit with said pipe contained in the axial boreof said drill bit from the breach in said wall when said drillingoperation has been completed.

2. A method as claimed in claim 1 wherein said cutting teeth are toolsteel.

' 3. A method as claimed in claim 1 wherein said cutting teeth arecemented carbide.

4!- Kraus 175403 X Sheiburne 77-69 Tilden 175-403 X Phipps 175-403Stcfies 175403 X Thatcher 175-94 CHARLES E. OCONNELL, Primary Examiner.

1. A METHOD OF REMOVING A PIPE EMBEDDED IN A MASONRY WALL WHICHCOMPRISES THE STEPS OF: (A) CONTACTING SAID WALL WITH SAID PIPE EMBEDDEDTHEREIN, AT THE POINT AT WHICH SAID PIPE IS EMBEDDED IN SAID WALL, WITHA ROTARY DRILL BIT HAVING AN AXIAL BORE AND A PLURALITY OF ELONGATEDCUTTING TEETH WHICH EXTEND SUBSTANTIALLY ALONG THE INTERIOR AND EXTERIORSURFACES OF SAID BIT AT THE LEADING END THEREOF AND WHICH ARE RIGIDLYATTACHED TO SAID LEADING END OF SAID BIT, SAID CUTTING TEETH HAVING ANINTERIOR DIAMETER OF FROM 10 TO 20 MILS LESS THAN THE OUTSIDE DIAMETEROF SAID PIPE, AND AN OUTSIDE DIAMETER GREATER THAN THE OUTER DIAMETER OFSAID BIT AND AN INNER DIAMETER LESS THAN THE INNER DIAMETER OF SAID BIT,SAID CUTTING TEETH HAVING A PITCH OF 0 TO 8 DEGREES, SAID BIT BEINGATTACHED AT THE TRAILING END THEREOF TO A ROTARY TOOL; (B) MOVING SAIDDRILL BIT COAXIALLY OF SAID PIPE SO AS THE AXIAL BORE OF SAID DRILL BITFROM THE BREACH IN BIT USING SAID PIPE AS A GUIDE MEANS FOR GUIDING THEMOVEMENT OF SAID DRILL BIT INTO SAID WALL AND COAXIALLY OF SAID PIPE INSUCH A MANNER AS TO REMOVE FROM 10 TO 20 MILS OF THE EXTERIOR SURFACEFROM SUCH PIPE DURING THE DRILLING OPERATION; AND (C) REMOVING SAIDDRILL BIT WITH SAID PIPE CONTAINED IN THE AXIAL BORE OF SAID DRILL BITFROM THE BREACH IN SAID WALL WHEN SAID DRILLING OPERATION HAS BEENCOMPLETED.